Technical Field
Embodiments of the present invention relate to an image processing system, an image generation apparatus, and an image generation method.
Background Art
An omnidirectional imaging system that uses a plurality of wide-angle lenses such as fish-eye lenses and super-wide-angle lenses to capture an omnidirectional image at a time is known (hereinafter, such an omnidirectional image is referred to as a spherical image) (see, for example, JP-2013-187860-A). Such an omnidirectional imaging system projects images from multiple lenses on the sensor plane, and joins these images together by image processing. Accordingly, a spherical image is generated. For example, two wide-angle lenses that have angles of view of 180 degrees or wider may be used to generate a spherical image.
In the image processing of JP-2013-187860-A, distortion correction and projective transformation are performed on the fish-eye images captured by lens optical systems, based on a predetermined projection model and in view of the distortion with reference to an optimal model. Then, the fish-eye images are joined together based on the overlapping portions included in the fish-eye images, and a sheet of spherical image is generated. In the joining process of the images, joining positions where subjects overlap with each other in the overlapping portions among the fish-eye images are detected using pattern matching or the like.